1. Field of the Disclosure
This disclosure relates generally to electronic devices, and particularly to manufacturing electronic devices having transistors with one or more channels.
2. Description of the Related Art
Scaling of device dimensions has been a primary factor driving improvements in integrated circuit performance and reduction in integrated circuit cost. Due to limitations associated with existing gate-oxide thicknesses and source/drain (S/D) junction depths, scaling of existing bulk MOSFET devices has proven difficult and therefore, alternate device structures, are likely to be needed to improve FET performance.
Transistors with alternative channel designs are particularly desirable if the transistor does not increase the layout area needed to form an improved transistor. As such, recent developments in transistor formation have brought about transistors having alternative channel designs. For example, one particular improvement is that of double-gate MOSFETs. The use of two gates to control the channel significantly suppresses short-channel effects. A fully depleted double-gate transistor has gates on both sides of a thin silicon layer for increased electrostatic coupling between the gates and the channel relative to the single gate device. One particular type of double-gate MOSFET is a FinFET. A FinFET is a double-gate structure that includes channels formed on both sides of a vertical silicon fin. Notably, FinFET transistors feature additional channel surface and thus increased current while at the same time reducing the leakage current.
Accordingly, there continues to be a need in the industry for transistors having alternate designs, particularly transistors that provide improved channel structures for better electrical responsiveness and higher currents while not adding to (or compromising) the layout area of the transistor.
The use of the same reference symbols in different drawings indicates similar or identical items.
Skilled artisans appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments.